Added '..' method for numbers to return an array with number ranging from \$self to \$arg;
Added 'join' method to join an array, with a speicified separator, as a string.
Added 'reverse' method to return an array reversed;
Sidef::Types::Array::Array->new() can take objects as arguments, puts them into an anonymouse array, and returns the blessed ARRAY ref. Before, it returned an empty blessed ARRAY ref.